About corn and grains and all of that:
I was recently reading about alll of these things that most dogs don't digest well. I don't have an exact link unfortunately but things like soy, corn, and wheat all aren't easily digested. Those are the worst things typically, but then like the by-products (like chicken beak?!) are also bad. I'll try to find a link, just so everybody can at least know what I'm talking about. I neverrr knew I was feeding my poor baby all this junk that upsets his belly.
A lot of people don't really bother switching their dogs to higher quality food to avoid all those things, but I did. I treat him like he's really my flesh and blood, regular old baby.
Edit: For the record, I have noticed his demeanor has changed since we changed his food. He's more energetic, more affectionate, less aggressive.
I'll be posting a picture of him soon.